Enhancing energy storage properties of Bi₄Ti₃O₁₂-based dielectric ceramics via doping BaSnO₃

In this work, (1 − x) Bi_2.8La_1.2Ti₃O₁₂₋xBaSnO₃ (x = 0.04–0.07, denoted as (1 − x)BLT–xBSN) ceramics were prepared using traditional solid-phase sintering technology at 1150 °C for 2 h. The introduction of BSN into BLT ceramics not only refines the grain, but also increases the Curie temperature (T_c), in addition to enhancing the dielectric temperature stability. In 0.95BLT–0.05BSN lead-free ceramics, the breakdown field strength reaches 210 kV/cm, and a recoverable energy storage density (W_rec) of 0.73 J/cm³ and an energy storage efficiency (η) of 86.7% are obtained. Furthermore, the 0.95 BLT–0.05 BSN ceramics showed good fatigue properties, with a 3.8% W_rec change over 10⁶ cycles at 20 °C, and, in particular, only a 3.6% W_rec change over 10⁶ cycles at 50 °C, demonstrating insensitivity to temperature changes. In addition, the reduction in ferroelectric polarization is attributed to the significant orbital hybridization between Bi/Ti and O atoms, along with the disorder in A/B site ionic displacements, as inferred from first-principles calculations.